Low-density parity-check (LDPC) codes are a class of error-correcting codes that may be efficiently encoded and decoded in hardware. LDPC codes are linear codes that have sparse parity-check matrices. The sparseness of the parity-check matrices allows for relatively fast decoding and computationally-inexpensive error correction. Many practical LDPC code designs use quasi-cyclic (QC) LDPC codes to yield more efficient hardware parallelization. Layered decoding is an efficient way of decoding LDPC codes and is commonly used in a wide range of applications. The number of cycles needed to process an entire layer of a base matrix associated with a QC LDPC code may depend on the hardware resources of the decoder.
Many existing LDPC decoders are preconfigured to support only a limited number of LDPC codes (e.g., for a particular communication standard). However, older LDPC codes are often phased out for newer LDPC codes as new communication standards are developed and existing standards are improved upon. Furthermore, some communication systems may use proprietary LDPC codes (e.g., for a backhaul network).